<html>
    <head>
        {% if title %}
            <title>{{ title }} - CSDN</title>
        {% else %}
            <title>welcome - CSDN</title>
        {% endif %}
    </head>
    <body>
        <div>
            My Website:
            <a href="{{ url_for('index') }}">Home</a>
            <a href="{{ url_for('login') }}">Login</a>
        </div>

        <hr>
        {% block content %}{% endblock %}
    </body>
</html>
